Kinetics of regeneration and maintenance of different populations of human cells in NOD/SCID mice between 2 days and 16 weeks after transplantation of 2 × 107 light density human marrow cells. (A and C) show the numbers of human cells (expressing the antigens indicated) that were found to be present in the marrow of two femurs and two tibias (solid symbols) or in the spleen (open symbols). In (C), CD19 refers to cells identified as CD34−CD19+ (most of the CD19+ cells seen were typically CD34−). (B) shows the numbers of human CFC and LTC-IC present in the two femurs and two tibias of the same mice, and (D) shows the percent of all nucleated cells in the blood of these mice that were human CD34+ or human (CD45/CD71)+ cells. In (A to C), the dotted line shows the number of cells of the type evaluated that were present in the original innoculum injected. Values shown are the mean ± SEM of results pooled from individually assessed animals (two to three animals per experiment) killed at the time points shown.
